Ernesto strengthened from a tropical storm earlier in the day, and the U.S. National Hurricane Center said it had sustained winds of 85 mph by early evening and was moving west-northwest at 18 mph. It was centered about 65 miles east of Chetumal.

Rain began falling in the afternoon in some places and streets flooded in seaside towns.

In the city of Tulum, some 6,000 tourists were sheltering in hotels away from the beach and authorities said the structures were strong enough to qualify as storm shelters.

Luana Antonicelli, a 23-year-old tourist from Melbourne, Australia, traveling with her 20-year-old brother, said they left their beachfront cabana surrounded by tropical jungle and decided to spend the night at the Hotel Tulum, a 20-room, one-story building about two miles inland.

"The people at our hotel told us to come into town because it's too dangerous to stay there," Antonicelli said.

She said most people at the Hotel Tulum were hunkering down inside their rooms even though it was only raining lightly Tuesday night. Hotel workers were distributing candles even though they still had electricity.

"It's a bit annoying because I want to be on the beach, but these things happen," Antonicelli said, adding that she and her brother decided to stay outdoors as much as possible. "I see it as an adventure."

Authorities also prepared two kindergartens in Tulum as shelters for up to 220 people, but only 20 people had showed up by Tuesday afternoon at one.

Cruz Garcia, a tourist guide, came to the shelter with his wife from Punta Allen, a low-lying coastal settlement.

"To be over there is a risk because the tide rises and there could be a disaster," Garcia said, adding that he twice went through strong hurricanes while living in the neighboring state of Campeche.

Soldiers and police evacuated all 600 residents of Punta Allen, and authorities were preparing for the evacuation of people from other low-lying coastal settlements, said Luis Gamboa of Quintana Roo's Civil Protection office.

Authorities in the Mexican state of Quintana Roo said more than 1,300 tourists were being moved from resorts in Mahuahal, Balacar and other spots to Chetumal, a bayside city that was expected to see less rain and wind than the coast. Two cruises ships scheduled to dock on the Riviera Maya put off their arrival.

The heart of the storm was expected to hit south of the resort areas of Cancun and the Riviera Maya, though strong rain and winds were likely. Officials prepared shelters as a precaution.

Forecasters said that after moving ashore during the night, Ernesto was expected to take about 24 hours to cross the Yucatan Peninsula and enter the southern Gulf of Mexico in an area dotted with offshore oil platforms owned by the state oil company Petroleos Mexicanos. Its predicted course would then take it to Mexico's Gulf coast near the city of Veracruz.

On its way to Yucatan, the storm swirled over open sea parallel to Honduras' northern coast, but officials there said the threat had passed without any damage or injuries.

Mexican authorities warned of possible flooding in some of the region threatened by Ernesto, where swollen rivers in the past have swept away houses, livestock and people and collapsed mountainsides.

Meanwhile, Tropical Storm Gilma formed in the Pacific Ocean about 620 miles west of Manzanillo, Mexico, with winds of 40 mph. The storm was not expected to threaten land.